Iron golf club set

ABSTRACT

An iron golf club set comprises a plurality of iron golf clubs having respective club numbers different from each other. Face progressions of the iron golf clubs become gradually smaller from the club having the smallest club number toward the other club having the largest club number in at least one group comprising a series of consecutively numbered clubs of the plurality of iron golf clubs.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an iron golf club set. Description of the Related Art In general, an iron golf club set is composed of a plurality of iron golf clubs having respective club numbers different from each other. The iron golf club set is composed for example of 10 clubs, i.e., seven iron clubs of No. 3 to No. 9 and three wedge clubs of a pitching wedge, an approach wedge and a sand wedge.

[0003] A face progression of each of these iron golf clubs has an influence on a trajectory of a golf ball hit by the golf club. Here, as shown in FIG. 2 illustrating a single iron golf club of the iron golf club set of the present invention, the face progression means a horizontal distance FP between a leading edge 5 and a vertical plane P, which faces in a flying direction of the golf ball hit by the iron golf club and passes the central axial line of a hosel 3.

[0004] Description will be given below of a face progression of each of the numbered clubs of the conventional iron golf club set with reference to FIG. 4. FIG. 4 is a graph illustrating a relationship between the numbered clubs of the conventional iron golf club set with their face progressions. An abscissa of the graph represents a number of the club and an ordinate represents a value of face progression. In FIG. 4, “X” indicates a straight line connecting values of face progression of the respective numbered clubs of the conventional iron golf club set (hereinafter referred to as the “prior art 1”) and “Y” indicates another straight line connecting values of face progression of the respective numbered clubs of the other conventional iron golf club set (hereinafter referred to as the “prior art 2”).

[0005] As is clear from FIG. 4, in the prior art 1, the face progressions of the respective numbered clubs of 10 iron golf clubs are kept constant. On the contrary, in the prior art 2, the face progressions of the iron golf clubs become gradually larger from a club having the smallest club number, i.e., the lowest lofted iron toward the other club having the largest club number, i.e., the highest lofted iron.

[0006] However, in the prior art 1, the face progressions of the respective numbered clubs, which are kept constant as a small value make the higher lofted irons relatively easier to use for hitting the golf ball, but make the lower lofted irons harder to use for hitting it, thus requiring a skilful technique for using such lower lofted irons efficiently. On the contrary, the face progressions of the respective numbered clubs, which are kept constant as a large value make the lower lofted irons relatively easier to use for hitting the golf ball, but make the higher lofted irons harder to use for hitting it, thus requiring a skilful technique for using such higher lofted irons efficiently.

[0007] In the prior art 2, the lower lofted irons, which have a small value of the face progression, make it hard to increase the trajectory of the resultant ball flight after being hit by the club. More specifically, when the face progression of the lower lofted iron is kept small in this manner, a golf club tends to be a so-called “gooseneck” shape. As a result, when a golf player hits a golf ball with the use of such a lower lofted iron, he has to place the golf ball near the intermediate position between the both feet. The above-described placement of the golf ball causes the inclination angle of the face of the golf club relative to the horizontal standard plane to increase so as to be in a so-called “closed face” condition, making it hard to increase the trajectory of the resultant ball flight after being hit by the club.

SUMMARY OF THE INVENTION

[0008] An object of the present invention is therefore to provide an iron golf club set, which makes it possible to increase easily the trajectory of the resultant ball flight after being hit with the use of any one of numbered clubs, especially a numbered club having a lower loft angle.

[0009] In order to attain the aforementioned object, an iron golf club set of the present invention comprises:

[0010] a plurality of iron golf clubs having respective club numbers different from each other,

[0011] wherein:

[0012] face progressions of said iron golf clubs become gradually smaller from a club having a smallest club number toward an other club having a largest club number in at least one group comprising a series of consecutively numbered clubs of said plurality of iron golf clubs.

[0013] A reduction ratio in the face progressions of the iron golf clubs may be expressed by a straight line.

[0014] A reduction ratio in the face progressions of the iron golf clubs may be expressed by a curved line.

[0015] The face progressions of all of said iron golf clubs may become gradually smaller from the club having the smallest club number toward the other club having the largest club number.

[0016] The plurality of iron golf clubs may be used for a right-handed golf player.

[0017] The plurality of iron golf clubs may be used for a left-handed golf player.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a partial front view illustrating one of a plurality of iron golf clubs forming an iron golf club set of the present invention;

[0019]FIG. 2 is a side view of the iron golf club as shown in FIG. 1;

[0020]FIG. 3 is a graph illustrating a relationship between numbered clubs of the iron golf club set of the present invention with their face progressions; and

[0021]FIG. 4 is a graph illustrating a relationship between numbered clubs of the iron golf club sets of the prior arts 1 and 2 with their face progression.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Now, an embodiment of an iron golf club set of the present invention will be described in detail below with reference to FIGS. 1 to 3.

[0023] The iron golf club set of the present invention is composed of 10 clubs, i.e., seven iron clubs of No. 3 to No. 9 and three wedge clubs of a pitching wedge, an approach wedge and a sand wedge.

[0024] Each of these clubs is composed of a shaft S, a head H fixed to the front end of the shaft S and a grip (not shown) fixed to the rear end of the shaft S as shown in FIG. 1. The head H is provided with a face 1, a sole 2, a hosel 3 and a back face 4.

[0025] The face progressions FP (see FIG. 2) of the iron golf clubs become gradually smaller from an iron golf club No. 3 serving as a club having the smallest club number toward an iron golf club No. 9 serving as the other club having the largest club number in a series of consecutively numbered clubs of the above-mentioned plurality of iron golf clubs, i.e., in the seven iron golf clubs No. 3 to No. 9. FIG. 3 is a graph illustrating a relationship between the numbered clubs of the iron golf club set of the present invention with their face progressions. An abscissa of the graph represents a number of the club and an ordinate represents a value of face progression FP.

[0026] As is clear from FIG. 3, the face progressions FP of the iron golf clubs become gradually smaller from the iron golf club No. 3 toward the iron golf club No. 9, respectively. A linear line having a minus slope as shown in FIG. 3 can express a rate of change in face progression. The face progressions FP of the remaining three clubs, i.e., the pitching wedge, the approach wedge and the sand wedge are kept constant.

[0027] Below is a table showing the relationship between the numbered clubs of the iron golf club set of the present invention, their loft angles L (see FIG. 2) and their face progressions FP. TABLE 1 Numbered club 3 4 5 6 7 8 9 PW AW SW Loft 19 22 25 28 31 34 38 43 49 55 angle (degrees) Face 11 10 9 8 7 6 5 5 5 5 progres- sion (mm)

[0028] As shown in Table 1, the face progressions FP of the seven iron golf clubs of No. 3 to No. 9 gradually decrease from 11 mm to 5 mm in this numbering order. The face progressions FP of the three wedge clubs, i.e., the pitching wedge, the approach wedge and the sand wedge are kept constant as the same value of 5 mm as the value of the face progression of the iron golf club No. 9.

[0029] According to the present invention described above, the iron golf club No. 3 serving as the low lofted iron has, for example, the face progression FP of 11 mm and the iron golf club No. 9 serving as the high lofted iron has the face progression FP of 5 mm, and the former face progression is remarkably larger than the latter face progression. As a result, it is possible for a golf player to place a golf ball in position, which is shifted toward its flying direction from the intermediate position between his feet so as to hit the golf ball in a sweeping motion with the use of the low lofted iron, irrespective of its low loft angle. It is therefore possible to increase the trajectory of the resultant ball flight after being hit by the club so as to impart specific properties to stop and stay easily on a putting green, even when the golf player uses the low lofted iron.

[0030] The iron golf club No. 6 serving as the middle-lofted iron has, for example, the face progression FP of 8 mm and the iron golf club No. 9 serving as the high lofted iron has the face progression FP of 5 mm, and the former face progression is larger than the latter face progression. As a result, it is possible for a golf player to place, in the same manner as described above, a golf ball in position, which is shifted toward its flying direction from the intermediate position between his feet so as to hit the golf ball in a sweeping motion with the use of the middle-lofted iron, irrespective of its relatively low loft angle. It is therefore possible to increase the trajectory of the resultant ball flight after being hit by the club, even when the golf player uses the middle-lofted iron.

[0031] The high lofted irons such as the iron golf club No. 9 have a loft angle of at least 38 degrees. As a result, it is relatively easy to increase the trajectory of the resultant ball flight after being hit by the club.

[0032] In the above-described embodiment of the present invention, the face progressions FP of the iron golf clubs become gradually smaller from the iron golf club No. 3 serving as the club having the smallest club number toward the iron golf club No. 9 serving as the other club having the largest club number in a series of consecutively numbered clubs of the plurality of iron golf clubs, i.e., in the seven iron golf clubs No. 3 to No. 9. The number of clubs forming the series of consecutively numbered clubs may optionally be changed. The face progressions FP of the iron golf clubs may become gradually smaller from the iron golf club No. 3 toward the iron golf club No. 8 for example in the six iron golf clubs No. 3 to No. 8.

[0033] The face progressions FP of the iron golf clubs may become gradually smaller from the club having the smallest club number toward the other club having the largest club number in all the plurality of iron golf clubs of the iron golf club set of the present invention.

[0034] The above-described iron golf club set of the present invention has a reduction ratio in face progressions of the iron golf clubs, which can be expressed by a straight line as shown in FIG. 3. The iron golf club set of the present invention may have a reduction ratio in face progressions of the iron golf clubs, which can be expressed by a curved line.

[0035] The iron golf club set of the present invention is described to be used for a right-handed golf player. The present invention may be applied to the iron golf club set, which is used for a left-handed golf player.

[0036] According to the present invention as described in detail, since face progressions of the iron golf clubs become gradually smaller from a club having the smallest club number toward the other club having the largest club number in at least one group comprising a series of consecutively numbered clubs of the plurality of iron golf clubs, it is possible to increase the trajectory of the resultant ball flight after being hit with the use of any one of numbered clubs, especially a numbered club having a lower loft angle. 

What is claimed is:
 1. An iron golf club set, which comprises: a plurality of iron golf clubs having respective club numbers different from each other, wherein: face progressions of said iron golf clubs become gradually smaller from a club having a smallest club number toward an other club having a largest club number in at least one group comprising a series of consecutively numbered clubs of said plurality of iron golf clubs.
 2. The iron golf club set as claimed in claim 1 , wherein: a reduction ratio in the face progressions of the iron golf clubs can be expressed by a straight line.
 3. The iron golf club set as claimed in claim 1 , wherein: a reduction ratio in the face progressions of the iron golf clubs can be expressed by a curved line.
 4. The iron golf club set as claimed in claim 1 , wherein: the face progressions of all of said iron golf clubs become gradually smaller from the club having the smallest club number toward the other club having the largest club number.
 5. The iron golf club set as claimed in claim 1 , wherein: said plurality of iron golf clubs is to be used for a right-handed golf player.
 6. The iron golf club set as claimed in claim 1 , wherein: said plurality of iron golf clubs is to be used for a left-handed golf player. 